Logs are not written to STDOUT even if log option points to it

[aladan12]

I've encountered a problem when trying to point logs toSTDOUT.
My options look like this:

      def server_options
        {
          log: "-",
          pid_path: pid_file,
          worker_type: "process",
          supervisor: true,
          daemonize: true,
          log_rotate_age: no_log_rotation,
          workers: workers_amount,
          restart_server_process: true
        }
      end

log: "-" points logs to STDOUT as per documentation https://github.com/treasure-data/serverengine/blame/master/README.md#L501
However this doesn't work and seems the root cause is here: https://github.com/treasure-data/serverengine/blame/master/lib/serverengine/daemon.rb#L87

Is there a way to make log: "-" option actually work?

Note: This is essential when logging into files is not appropriate e.g. dockerization.